But failures and funding problems have not deterred the adventurer. Two weeks ago the company announced it was increasing the new satellite launcher’s performance, and have now publically said they have made “significant progress” on the engines.

Above is what the liquid rocket propulsion system that will power Virgin Galactic's small LauncherOne looks like.

The NewtonThree main stage engine ran for a total of 20 seconds at custom-built test stands in Mojave, California, during which it experienced steady operation and allowed the team to run tests, before shutting down. The upper stage engine was tested earlier in the week.

Initially, the company planned to use LauncherOne to send payloads only slightly exceeding 200kgs. Now the company says that the improvements made to the launcher spacecraft enable it to carry up to 400kgs into low Earth orbit, and about 200kgs into sun-synchronous orbit, used by remote sensing satellites.